Elastic-fluid turbine.



No. 700,744. Patented May 27, 1902; c. a. cunns. ELASTIC rum) TURBINE.

(Application med Inn. 12, 1898.) illolodl.) 6 Shoots-Sheet l.

No. 700,744. Patented May 27,

' O. G. CURTIS.

ELASTIC FLUID TURBINE. (Appli ution filed a. 12, 189B.)

6 Shasta-Sheet 2.

(No Model.)

Inventor Patented May 27, I902. C. G. CURTIS.

ELASTIC FLUID TURBINE.

(Application filed Jan. 12, 1898.)

6 Sheets-Sheet 3.

Jnventpr 64.04,, 41. W

(No Model.)

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No. 700,744. Patented May 27, I902.

c. G. CURTIS.

-ELASTYIC FLUID TURBINE.

(Application filed Jan. 12, 1898.)

' Jnven for Patented May 27, I902. v

(Application filed Jan. 12, 1898.)

6 SheetsS heet 5.

(No Model.)

may 1/ W, I. v 7 I gwwwwv w wv ww Jnve n to Patented May 27, I902.

c. a. CURTIS.

ELASTIC FLUID TURBINE.

(Application filed Jan. 12, 189B.)

6 Sheets-Sheet 6,

(No Model.)

\N MWN .[ru/erz for Win 66666.

UNITED STATES CHARLES G. CURTIS, OF NEW YORK,

MENTS, TO CURTIS STEAM TURBINE WEST VIRGINIA.

N. Y., ASSIGNOR, liY MESNE ASSIGN- UOMIANY, A CORPORATION OF ELASTIC-FLUID TURBINE.

SPECIIIGATION' forming part of Letters Patent No. 700,744, dated May 27, 1902. Application flied January 12, 1898. Serial Ko- 666,379. No model.)

To all whom, it ntay concern:

Be it known that I, CHARLES G. CuR'rrs, a citizen of the United States, residing at New York city, in the county and State of New York, have invented a certainnew and useful Improvement in Elastic-Fluid Turbines, of which the following is a specification.

My invention relates to an improvement upon governors for elastic-fluid turbines involving the invention described and claimed in my Patent No. 566,967, wherein regulation is. efle'ctedwithout material loss of efliciency by varying the volume of the elastic fluid without substantial variationof its velocity at the point or points where it acts upon the movable elements or vanes of the turbines. It involves among other features an improvement inthe device vshown inFigure 6 of said patent-namely, a partitioned nozzle having more or fewer of its divisions or sections closed or opened as the lead decreases or increases.

In carrying out my' invention I employ a form of delivery-nozzle in which the nozzle is divided up into a." number of separate sections, and these separate sections are brought together in a single structure or made into a single casting with their discharging ends appronimated so'closely thattheflnid isdelivered by the several sections to the buckets in the form of a substantially solid body or stream.- These sections are preferably substantially alike in form and in angle of-delivery,each section having a throat and walls leading from' said throat to the discharging end of the nozzle, which walls may or may not afford an en-' larg'ingcross-section. of passage, according to the degree of conversion of pressure into c-is viva desired. The nozzle-sections are also preferably provided with separate enlarged supply chambers anterior to the threats. Separate steam passages or pipes extend from the sections of the nozzle backto a connection with the steam-boiler or other source of elastic fluid ujnder'pressure, and these passages I make controllable by means of a valve or valves, so as not only to vary the number of sections receiving the elastic fluid, but to throttle and regulate the flow through a single section acting in conjunction with ethos ml} sections. Th passages are preferably allextended toa valve-case, and the number of sections of the nozzle in operation is deter-.

mined by a valve, preferably moved bya speed-governor. This valve in'moving across the ports connected with the sections ofthe nozzlewill progressively open or close the ports in succession, so that at no time will more than one section of the nozzle be throttled'with reference to the fluid-supply, and thus permit expansion of the fluid under inefiicient conditionsin that section; butI have found that with a nozzle composed of a number of sections 'this loss of eificiency is only a small percentage of the entire-172's vivadeveloped, and hence the velocity of the elasticfiuid body as a whole will be maintained without substantial variation during the gradual changes in its volume :orquantity which are effected by the valve progressively opening or closing the sections of the nozzle. By controlling the flow of steam in this manner I am enabled to obtain quite a high average efliciency under a widely-varying load even with only a few sectional divisions of the nozzle, because underall' conditions except those of very small load a number of the sections will be operating at their maximum efficiency and only one of the sections can be working with a lower efliciency. In other' words, the total vis viva developed in the nozzle is produced by a number of sections working at full eificiency and perhaps one additional one working'with an efiiciency which varies in accordance with the slight changes in power; but it will he observed that where the additional section is doing but a slight amount of work and working at comparatively low efficiency the work contributed by it to that of the other sections is such a small fraction of the whole that a considerable sacrides in eificiencyof this section causes an unimportant reduction in the efficiency of the nozzle as 'a whole. Similarly while this additional section is working at aconsiderable fraction of its full capacity its efficiency is 'quite high, so that by moreor less throttling only one oi the sections at a time 1am onabled to obtain a close regulation with quite a high average efiiciency under all conditions except those of very light load. By increastel ing the number of sections, which of course can be done indefinitely, a more uniform efthe turbine wheel. It is, however, also ap-- plicable to elastic-fluid turbines of that class in which the ring of buckets receives the clastic fluid simultaneously throughout its entire circumference when developing its maxim um power, a portion only of the ring of buckets receiving fluid when less than the maximum power is being developed. In such a case the nozzle will occupy the entire circumference of the turbine and be divided into any desired number of sections, and the 'independe'ntpassages from the sections of the nozzle to the source of supply may be controlled by hand or automatic valves or partly by handvalves and partly bfautomatic valves. The separate sections composing the complete sectional nozzle may all be of the same size or of different sizes, butshould be of like form. I have applied my improved sectional nozzle also to my in nltiple-stage elastic-fluidturbine, wherein the movable vanes are divided between two or more shells working at different initial pressures, as described in my Patent No. 566,969, as well as to arrangements for operating the same turbine (whether having one shell or two or more shells) either as a condensi'ng'or non-condensing engine.

My improved sectional nozzle has the advantage over the divided nozzle shown in Fig. 6 of my Patent No. 566,967 in that byvmaking a sectional nozzle composed of a number of independently-complete sections all alike the length of the walls from the'throat to the discharging end of the nozzleis greatly diminished and the loss from surface friction is lessened, and, further, the improved sectional nozzle is provided with a more practical audsimple, and therefore more desirable, form of valve mechanism. In my i'm- By making the cross-section of the throata cirole, as shown in some of the drawings herein, I am enabled to obtain a minimum of surface exposed as compared with the volume or quantity of steam and a better throat action is also secured, thus affording a more satisfactory device for converting pressure into 'vis riva. It will be observed, however, that in this improved sectional nozzle, as in the divided nozzle of the patent referred to, the elastic fluid is discharged from theseveml sections of the nozzle as a practically continuous body or stream. If the discharge ends of the sections of the nozzlefwere separated or if the turbine had several separated nozzles, the stream issuing from each section or from each nozzle would inadequately fill the two buckets exposed toit at the ends of its side walls, thus causing inefiicient action in these two buckets. This loss of efiiciency would be multiplied by the number of separated sections or separate nozzles, but is reduced to a minimum by bringing the ends of the sections close'together and separated each from the other by a thin partition only, the columns of fluid on the two sides of each partition uniting as they leave the edge to form a solid body or stream of fluid, the thin partitions causing no gaps between the several sections of the vstream. .This feature becomes very important in a jet-turbine, and its importance increases as the working passage is more and more compounded.

In the accompanying drawings, forming a part-hereof, Fig. 1 isahorizontal section showing my improved sectional nozzle applied to a compound jet-turbine, such as that of my Patent'No.5 66,968. Fig.2 is an elevation illustrating the discharging end of the nozzle. Fig. 3 is an outline sketch illustrating on a larger scale the form of one of the nozzle-sections composing the sectional nozzle. Fig. 4 is a sectional view through two of the nozzle-sections on the line 4 Lin Fig-1 and lookiug in the direction of the arrow at that line. Fig. 5 is a vertical section following the line of one of the steam-passages. Fig. 6 is a horizontfil section illustrating the invention applied to a double-shell jet-turbine, such as that of my Patent No. 566,969. Fig. 7 is a plan view, of the construction illustrated in Fig. 6. Fig. 8 is a horizontal section of my improved nozzle applied to a turbine adapted to operate either as a condensing or a noncondensing engine, such as isdescribed in my Patents Nos. 589,466 and 590,210, the ports,

in the governing-valve being arrangedat right angles to those of the valve shown in Fig. 1. Fig. 9 is a partial end view showing the improved sectional nozzle applied to a turbine whose entire circumference is utilizedfor the admission of the elastic fluid. Fig. 10 is a view in outline in which the sectional nozzle of Fig. 9 is partly developed in ahorizontal plane; and Fig. 11 is an end view of the discharging-nozzle ofFig. 9, all sections of the nozzle being of thesame size.

Referring particularly to Figs. 1 to 5, inclusive,-A is the shell of the turbine, in which rotates a. wheel B, carrying one or more sets of movable vanesC 0 (two being herein shown also) and a set of stationary intermediate vanes 8*, as will be understood by reference to my prior'patents. Dis the exhaust-port of. the turbine, opening directly into the air or connected with a condenser. Secured in an opening in the shell, soas to deliver a jet of elastioiluid to the first set of vanes C, is a cored casting E, forming my improved sectional nozzle. This is composed of a number of short sections F, provided with contracted throats a and having supply-chambers larger than the throats anterior thereto and with walls which converge to form the throats and also having posterior to the throats diverging walls which extend to the discharging ends of the sections, at which points the separating-walls are made so thin that the elastic fluid unites when discharged from the several sections and forms a practically continuous body. Attached to'the casting E or made integral with it is another casting G, carrying a number of steam-passages E, one for each of the nozzle-sections F, which steam-passages extend back to the ports I; in the valve-case H. The valve-case H is provided with a closing-casting H and with heads 0. These parts E, G, and H being all castings may be divided at any suitable points into any desired number all; parts to secure cheapness and perfecs tion in manufacture. The passages F start with the oblong ports I; of rectangular form and are of suflicient area to permit the desired quantity of fluid to'fiow without objectionable loss of pressure, and the passages cause no loss in pressure and gradually become of circular cross-section, which is maintainedup to the contracted threat a of the nozzle-sections, as illustrated in Fig. 4, and from the throat the sections are gradually drawn into a rectangular form toward their discharging ends, increasing in cross-section from the throats to the discharging ends, so as to give a further expansion of the elastic fluid and a .further conversion of pressure into velocity. It the n'ozzle is one having no expansionthat is, no enlargement in crosssectional area from the t roat to the discharging end-then the throat ust either-be made of a rectangular form having the same area as the rectangular end of thenozzle, or if the throat be circular in rm its diameter must be such as to give an area equal to the area of the rectangular discharging end of the nozzle. Back of the throat or the passages F shouldtheoretically have the form illustrated by the dotted lines in Figs. 3 and 4; but since by giving them this form one passage would encroach upon another the lower wall of each passage is slightly flattened, as illustrated by the full lines. Within the'valvecase H is the valve 1, having two circular heads or pistonsdd, which are always on opposite sides of the steam-inlet J, and hence balance the valve. The head 41 plays across the ports b and has an angular or oblique face where it rides over the ports, as illus: trated in Fig. 8, so that at the instant of completely closing or opening one port it begins to close oropen the next port it moved farther in the same direction. The ends of the valve-case outside of the heads of the valve are connected together by a passage e and may be connected with the shell of the turbine by a pipe 1, so that any eakage past leakage will find its way into the shell through the nozzle-passages.

Referring particularly to Figs: 6 and 7,

showing a compound double-stage turbine, as

described in my Patent No. 566,969, A and A are two shells, each containing one or more sets of movablev vanes, two sets in eachshell being illustrated. One of-my-improved sectional nozzles and controlling-valves is conneeted with each shell, the valve-case for controlling the sectional nozzle of the second shell having its inlet-pipe connected with the exhaust of the first. shell. The two valvestems I P are operated simultaneously by the same speed-governor K b "means of a. lever -g, connected by links h with bell-cranks first stage he worked with an exhaust of approximately atmospheric pressure, provision may be made for connecting this exhaust to the atmosphere, as illustrated in dotted lines in Fig. 6, was to utilize the method-of working the turbine either as a condensing or noncondensing engine, which is described specifically in my Patent No. 590,211. conditions the volume of the steam will be, roughly speaking, nine times greater at the second valve-case than at the first valve-case, and with the enlarged construction which this increased volume requires the second controlling-valve may have a movement three times as great as the first controlling valve. These proportions are intended to be illustratedin Figs. 6 and 7.

In Fig.8 I have shown .a single shell A, provided with a wheel B, having two sets of movable vanes C 0 and having two sets of intermediate stationary passages 0 0', which operate in conjunction with two of my improved sectional nozzles L L' and two exhaust-portsD D". The nozzle L is adapted to give the elastic fluid that degree of expansion which is required for working the turbine as a condensing-engine, while the nozzle L gives a lower degree of expansion, such asis required for-working the turbine as a noncondensing engine,the intermediatepassages C and C being also properly proportioned, as described in. my Patent No. 590,210. The valve-easeTH has a single set of ports b, which Under such.

are connectedwith the passages extending to both .nozzles, and these passages are provided with hand-operated valves M for opening and closing them, so that the passages leading to one of the sectional nozzles may be closed while the other nozzle is in operation.

It is 'evident that the constructions illustrated 'in Figs. 1 to 8, inclusive, could all be employed in the same turbine. The separation of the illustrations is made to avoid confusion.

Referringparticnlarly to Figs. 9, l0, and 11, the sectional nozzle is illustrated as one which occupies the entire circumference of, the turbine, and when all the sections of the nozzle are opened and the turbine is developing its maximum, power the elastic fluid is delivered simultaneously throughout the one tire circumference of the turbine. The several sections F meet at their discharging ends, or substantially so, in order that the elastic fluid delivered by two adjacent sections of thenozzle may unite into a continuous body of -fluid at the point of discharge from the nozzle.- The separate sections of the nozzle are connected with the common steam-supply pipe N and are controlled by hand-valves O,

which maybe operated automatically, if de-- sired. The sections may be made'ot different sizes, as-is indicated in the, drawings, where the sections-F are ofsmaller size.

I also propose to use my improved sectional nozzle in the elastic-fluid compressor upon which I have applied for a tion Serial No. 601,606.)

What I claim is- 1. The sectional nozzle for elastic-ii uid turbines herein described, consisting of a number of separate complete nozzle-sections each.

having a contracted throat, and a supplychamber anterior to and larger than said throat, such sections being brought close together at their discharge ends, whereby the several separate jets'or streams merge intoa substantially single jet orstream at' the'points of discharge, substantially as set forth. I

2. The sectional noz'zle for elastic-fluid turbines herein described, consisting of a number of separate complete nozzle-sections each having a contracted throat, a supply-cham-z ber anterior to and larger than said throat, and a discharging portion posterior to said I throat, said sections being brought close together at their discharge ends, whereby the several separate jets or streams merge into a substantially single jet or stream at the points of discharge, substantially as set forthbines herein described, consisting of a num-' ber of separate complete nozzle-sections each having a contracted throat, a supply-chamber anterior to and. larger than said throat, and a dischargingportion posterior to and en.- larging beyond said throat, such sections being brought close together at their discharge ends, whereby the several separate jets or streams merge into a substantially single jet patent, (applicaor stream at the points of discharge, substan tially as set forth.

4. In an elastic-fluid turbine, a sectional nozzle consisting of a number ofseparate coinplete'nozzle-sections each having a contracted throat, a supply-chamber anterior toand larger than said throat, and a discharging portion posterior to and enlarging beyond 'said throat, such sections being brought close together at their discharge ends, whereby the several separate jets or streams merge into a substantially single jet or stream at the points of discharge, in combination with means for admitting the elastic fluid to or shutting i off from more or'less of said nozzle-sectious substantially as set forth.

.5.- In' an elastic-fluid turbine, a sectional nozzle consistingof a number of separate complete nozzle-sections'each having a contracted throat,'a-supply-chamber anterior to and larger than said throat, and adischarging portion posterior to'and enlarging beyond said throat, such sections being brought close together at their discharge ends, whereby the several separate jets or streams merge into a substantially single jet orstream at the points of discharge, in combination with a number of separate supply-passages, a valve-case with ports for such separate passages, and a valve in such valve-case opening and closing said ports progressively, substantially as set forth.

6. In an elastic-fluid turbine, a deliverynozzle coinprisingsections substantially alike in form and in angle of delivery and brought close together at their discharge ends, whereby the jetsor streams from adjacent sections merge into a substantially single jetor stream at the points of discharge, in combination with means'for admitting the elastic fluid to or shutting it of! from more or less of said sections, substantially as set forth.

7. In an elastic-fluid turbine, a deliverynozzle comprising sections substantially alike in form and in angle of delivery and brought close together'at their discharge, ends, where- 'by'the'jets or streams fromadjaoent sections merge into a substan tialiy single jet or stream at the points of discharge, in combination with a plurality of separate supply-passages extending back from said nozzle-sections, and

means for admitting the elastic fluid to or shutting'itofli'from more or less of said supply-passages, substantially as set forth.

' I 8. In an elastic-fluid turbine, the combination with two or more shells having movable vanes and receiving the-elastic fluid'in s cession ,of a delivery nozzle' for each shell com 3. The sectional nozzle for elastic-fluid turprising sections substantially alike in form aud'in angle ofdeliveryand brought close together at their discharge ends, whereby the jets or streams from adjacent sections merge into a substantially single jet orstream at the points of discharge, valves for admitting the elastic iiuid'to or shutting it of! from more or less of the sections of each-nozzle, and means for moving said valves coordinately, substantially as set forth.

9. In an elastic-fluid turbine, the combination with two or more shells having movable vanes and receiving the elastic fluid in succession,of a deliver -nozzle for each shell comprising sections substantially alike in form and in angle of delivery and brought close together at their discharge ends, whereby the jets or streams from adjacent sections merge into a substantially single jet or stream at the points of discharge, a plurality ofseparate supply-passages extending back from the sections of said nozzle, valves for admitting the elastic fluid to or shutting it off from more or less of the supply-passages of each nozzle, and means for moving said valves coordinately, substantially as set forth.

10. In an elastic-fluid turbine, the, combination with two 'or more shells containing movable vanesand receiving the elastic fluid in succession, of delivery-nozzles of successively-greater cross-sectional areajbr. the two or more shells, each of such delivery-nozzles comprising sections brought close together at theirdischarge euds,a plurality of'supply-passages for the sections of each nozzle, valve mechanisms acting to open and close such supply-passages, such valve mechanisms having successivelya greater movement for the same degree of regulation, and means causing the valve mechanisms to work coordinately so that the two or more nozzles shall be proportion- :fttely opened. and closed, substantially as set orth.

11. In an elastic-fluid turbine, the combination of a number of separate supply-passages and separate complete nozzle-sections proportioned for the degree of conversion of pressure into velocity required for condenslug-work, and a'number of separate supplypassages and separate complete nozzle-sections proportioned for the degree of conve'r sion ot pressure into velocity required For non-condensing work, and valves-for closing the supgly-passage to one set of nozzle-sections w on the supply-passages to the other set of nozzle sections are opened, substantially as set forth.

12. In an elastic-fluid turbine, the combination of a number of separate supply-passages and separate complete nozzle-sections proportioned for the degree of conversion of pressure into velocity required for condenslug-work, and a number of separate supplypassages and separate complete nozzle-sections proportioned for the degree of conversion of pressure into velocity r uired for non-condensing work, valves for c osing the upply-passages to one set of nozzle-sections when the supply-passages t: the-other set of nozzle-sections are opened, and agoverning or controlling valve common to the supply passages of both sets of nozzle-sections for conformed by partitions separating the sectionswhich are thicker at the throats than at the discharge ends of the sections, substantially as set forth.

14. In an elastic-in id turbine, separate supply-conduits leading from a source of fluidsupply under pressure to two or more expansion delivery-passages delivering the fluid to the same set of buckets, in combination with valve mechanism automatically actuated by a speed-governor for admitting the fluid to and excluding it from the supply-conduits in succession, the valve mechanism opening and. closing each conduit successivelybydegrees, substantially as set forth.

15. In an elastic-fluid turbiue,a nozzle the cross-sectional perimeter of whose throat is curved, said nozzle having a rectangular discharging end in combination with a rotating turbine-wheel, substantially as set forth.

16. In an elastic-fluid turbine, a nozzle whose throat has a curved cross-sectional perimeter and having expanding or diverging walls which gradually draw into a rectangn lar form at the discharging end of the nozzle, substantially as set forth.

17. In an elastic-fluid turbine, a sectional nozzle, the throats of the several sections having a curved cross-sectional perimeter, and the discharge ends being rectangular, in combination with a rotating turbine-wheel, substantially as set forth.

'18. In an elastic-fluid turbine, a sectional nozzle, the throats of the several sections having a curved cross-sectional perimeter and opening into expansion delivery-passages whose diverging walls gradually draw into a rectangular form at their discharge ends, substantially as set forth.

This specification signed and witnessed this 7th day of January, 1898.

CHARLES G. CURTIS.

Witnesses:

EUGENE Comma, Jrro. R. TAYLOR.

Correction in Letters Patent No. 700,744.

It is hereby :zz'fiivi 13119.4; in Letters Patent No. 100,744, granted May 27, 1902, upon the application of Charles G. Curtis, of New York, N Y., for an improvement in f Elastic-Fluid Turbines, an error appears in fhe printed specification requiring correction, as follows: .In line 21, page 1, the word lead should read load; and that 1 the said LettersPatent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 3d day of June, A. D., 1902.

[sEAL] F. I. ALLEN,

Commissioner of Patents. 

